v3.26.1
Note 10 - Stock-based Compensation Stock (Tables)
6 Months Ended
Jun. 30, 2026
Notes Tables  
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
   

Three Months Ended June

30,

   

Six Months Ended

June 30,

 
   

2026

   

2025

   

2026

   

2025

 

Research and development

  $ 137,175     $ 121,159     $ 263,885     $ 244,861  

General and administrative

    225,100       375,856       447,586       613,321  

Total stock-based compensation expense

  $ 362,275     $ 497,015     $ 711,471     $ 858,182  
Share-Based Payment Arrangement, Option, Activity [Table Text Block]
   

Number of

Options

   

Weighted

average

exercise price

per share

   

Weighted

average

remaining

contractual life

(in years)

   

Aggregate

intrinsic value

 

Balance at January 1, 2026

    992,701     $ 11.76       8.0          

Granted

    356,350       4.49                  

Exercised

    (6,000 )     2.30                  

Expired

    (2,219 )     184.41                  

Forfeited

    (195 )     5.33                  

Outstanding at June 30, 2026

    1,340,637       9.59       7.6        

Exercisable at June 30, 2026

    747,134       12.96       6.4        
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
   

Six Months Ended June 30,

 
   

2026

   

2025

 

Expected term (in years)

  5.26 - 5.75     5.24 - 5.76  

Risk-free interest rate

  3.83 - 4.31%     3.93 - 4.35%  

Expected volatility

  67.99 - 69.73%     71.55 - 76.68%  

Dividend yield